Contents
What causes increased drag?
Drag increases with the density of the fluid (ρ). More density means more mass, which means more inertia, which means more resistance to getting out of the way. The two quantities are directly proportional. Drag increases with area (A).
What causes rain aviation?
Rainfall occurs when the air becomes saturated, either through cooling or by the addition of water, to form a cloud. Cooling of the air may be caused by a variety of means, for example, due to up-currents or when the air moves over a rising surface.
What are the main causes of aerodynamic drag?
We can think of drag as aerodynamic friction, and one of the sources of drag is the skin friction between the molecules of the air and the solid surface of the aircraft. Because the skin friction is an interaction between a solid and a gas, the magnitude of the skin friction depends on properties of both solid and gas.
What are the negative effects of cloud seeding?
Risks or concerns like unwanted ecological changes, ozone depletion, continued ocean acidification, erratic changes in rainfall patterns, rapid warming if seeding were to be stopped abruptly, airplane effects, to name a few, may just not be bad enough to override the imperative to keep temperatures down.
What causes freezing rain aviation?
Freezing Rain occurs when precipitation, in the form of rain, passes from a warm air mass into a relative cold air mass of an air temperature less than 0°C32 °F <br />273.15 K 491.67 °R . The rain maintaining its liquid state in sub-zero temperatures renders it super-cooled.
Is cloud seeding harmful to the environment?
Silver iodide, the material used in cloud seeding, is toxic to aquatic life. So precipitation from seeded clouds can harm the environment. In response to these concerns, scientists have tested nontoxic replacements for silver iodide. They have found calcium chloride to be effective.
Who invented cloud seeding?
Vincent J. Schaefer
Vincent J. Schaefer, a self-taught chemist who invented cloud “seeding” and created the first artificially induced snow and rainfall, died on Sunday at a hospital in Schenectady, N.Y. He was 87 and lived in Rotterdam, N.Y. Mr.
Can airlines fly in freezing rain?
Generally airline and passenger/freight carrying operations are suspended during periods of freezing rain. Even without being prohibited by the operators manual, operations in freezing rain are difficult as the applicable Hold-Over Time from an anti-icing treatment is very limiting in freezing rain.
What are frozen raindrops called?
Sleet
Sleet is less prevalent than freezing rain and is defined as frozen raindrops that bounce on impact with the ground or other objects.
Drag is influenced by other factors including shape, texture, viscosity (which results in viscous drag or skin friction ), compressibility, lift (which causes induced drag ), boundary layer separation, and so on.
How does the drag of an object increase with speed?
Drag increases with speed ( v ). I hope that this is self-evident. An object that is stationary with respect to the fluid will certainly not experience any drag force. Start moving and a resistive force will arise. Get moving faster and surely the resistive force will be greater.
Why is the force of drag called induced drag?
The force is called induced drag because it has been “induced” by the action of the tip vortices. The magnitude of induced drag depends on the amount of lift being generated by the wing and on the distribution of lift across the span. Long, thin (chordwise) wings have low induced drag; short wings with a large chord have high induced drag.
How is drag generated in a gravitational field?
It is not generated by a force field, in the sense of a gravitational field or an electromagnetic field, where one object can affect another object without being in physical contact. For drag to be generated, the solid body must be in contact with the fluid. If there is no fluid, there is no drag.